Preheat oven to 450 degrees. Season chicken with salt and pepper. In a large, straight-sided ovenproof skillet, melt butter over medium-high heat. Add chicken to skillet, skin-side down; cook until golden brown, about 5 minutes a side. Transfer to a plate.

Reduce heat to medium. Add leeks to skillet; cook, stirring frequently, until softened, about 4 minutes. Stir in wine; cook until almost evaporated, 1 minute. Add broth and potatoes; season with salt and pepper. Bring to a boil, then add chicken, skin-side up; transfer to oven. Roast 15 minutes, then remove and add asparagus; season with salt. Cover and return to oven; roast until potatoes are tender and chicken is cooked through, about 10 minutes more. Transfer chicken to a plate. Stir cream into skillet, then return chicken. Serve, with dill.